As described by Davis, I. A. et al in the article “Comparison of Actinium 225 Chelates: Tissue Distribution and Radiotoxicity” published in Nucl. Med. Biol., Vol. 26, pp 581–589, 1999; by Deal, K. A. et al. in the article “Improved in Vivo stability of Actinium-225 Macrocyclic Complexes” published in J. Med. Chem., Vol. 42, pp. 2988–2992, 1999, by Grote Gansey, M. H. B. et al. in the article “Conjugation, Immunoreactivity, and Immunogenicity of Calix (4) arenes; Model Study to Potential Calix (4) arenes—Based Ac3+ Chelators” published in Bioconj. Chem., Vol. 10, pp 610–623, 1999, and by Ouadi, A. et al. in the article “Synthesis of a novel Bifunctional Chelating Agent for 225Ac complexation” published in Tet. Lett., Vol 41 pp 7202–7209, 2000, a bifunctional chelating agent is necessary to bind with a good stability a radionuclide to a vector.
An object of the invention is to provide more effective bifunctional chelating agents for metals especially actinides and lanthanides.